Remediation of zinc from mine tailing using electrokinetic method combined with washing solvents

Abstract

Mining activities have resulted in a large amount of mineral tailings, which are potentially toxic and hazardous metals that contaminate the soils surrounding the mines. Because of the negative effects of potentially toxic elements on natural ecosystems, efficient solutions for soil and mineral tailings remediation are required. Several tailings samples were taken from various parts of the Anguran zinc mine to investigate the efficiency of electrokinetics. The total concentrations of soil elements were then determined using the standard ICP method. Several washing solutions with a fixed concentration of 0.1 M were used to assess the efficiency of electrokinetics in soil. The washing solutions included hydrochloric acid, nitric acid, acetic acid, and sulfuric acid. The solutions were mixed with soil in a 1:2 solution-to-solid ratio. Furthermore, for all experiments, a voltage of 1.5 V/cm was used. To prevent heavy metal deposition in the soil near the cathode chamber, the designated chemical filtration solutions were also used in the cathode chamber at a fixed concentration of 0.1 M. The experimental results revealed that metals such as zinc and lead were present in varying degrees in the tailed soil. The zinc heavy metal had the highest concentration in the tailed samples. The lowest zinc removal efficiency was obtained with distilled water, with a metal removal of 16%, indicating that electrokinetic remediation in soil has little effect. Our findings also show that electrokinetic soil remediation using a hydrochloric acid complexing agent is more effective than other agents, and that it can remove up to 64% of the zinc from mine tailing soil.